


Ocean's Call

by naventho



Category: Undertale (Video Game)
Genre: Alphynecentric, Angst, Anxiety, Depression, F/F, Fluff, Suicidal Thoughts, That's it, also there's a pretty graphic description of alphys nearly drowning so that might be an issue, but otherwise it's really fluffy, human au (for alphys), i mean asgore is kind of mentioned but he's not even named, i mean it's really minor but they're at least alluded to so be careful if that stuff bothers you, mermaid au (for undyne)
Language: English
Status: Completed
Published: 2015-12-30
Updated: 2015-12-30
Packaged: 2018-05-10 11:07:50
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 6,576
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5583499
Author URL: https://archiveofourown.org/users/naventho/pseuds/naventho
Summary: <blockquote class="userstuff">
              <p>Alphys didn't expect a trip to the beach to change her life.</p>
            </blockquote>





	Ocean's Call

**Author's Note:**

> Sorry for not updating Home all this time! I've been working on this fic. I got the idea when I realized Undyne is really similar to the word undine (which was probably on purpose) and mermaids are a subcategory of undines and it just went from there! I'll get back to writing Home, so expect an update soon from that, too.  
> Also, warning for a semi-graphic description of drowning and suicidal thoughts. They're like 5% of the fic but be careful anyway if you have trouble with things like that.

The first time Alphys saw her, the ocean was tempestuous and the wind was biting. The sky was-steel grey. The sound of crashing waves filled her ears, and she could taste salt every time she took a breath.

It was going to storm. She knew that. For some reason, she waded into the shallows anyway, searching for marine life she could collect to study later. Maybe it was because, after the accident, she just couldn't stay away- and maybe that had to do with the fact she suddenly had very little motivation to do anything else.

An especially strong wind blew, and she squinted as she gazed out across the sea. She could only imagine what kinds of animals thrived in the water- what kind of unimaginable creatures lived at the very depths. Scientifically, the ocean fascinated her. All living things could trace their roots back to it, and plankton produced so much oxygen that it continued to foster life even on land.

Oceanic biology was incredibly interesting to her as well. By taking some of the organisms she found home to study, she felt a connection with the sea that she treasured, even if she didn't especially like going outside. Especially after the accident, she always felt out-of-place when she was anywhere but in her home. As hidden away as possible.

Well, she felt that way anywhere but there and at the ocean, at least.

She glimpsed the arm of a starfish in the sand and started toward it. Just as she neared, she felt the pull of the tide change, and her feet begun to slip from under her.

Her heart seemed to stop in her chest. The water was above her knees. She was too deep.

She turned toward the shore, quickly trying to reach it before it got worse. She had only heard of things like these happening. She pushed against the water harder.

The more she struggled, the harsher the waves seemed to pull. The sand underwater buffed against her legs and slowed her down as it rushed out to the sea. Her heart hammered in her throat as she got forced farther and farther away, her hands clenched the bag so tightly that her knuckles were while, her breathing nearly stopped as she was pulled to where sandbar ended, falling deeper and crashing into the cold, cold, _cold_ embrace of the merciless sea.

Alphys' eyes burned under the water, but she forced them open and fought to reach the surface. Her glasses had been knocked off by the current- she couldn't see a thing. Legs burning, heart hammering, she pushed with all her might toward the sky, icy panic shooting through her veins. She couldn't die here. She couldn't die here. She couldn't...

Her limbs grew heavier and heavier until she found she could hardly move them anymore. The weight of the water dragged down on her. The cold had seeped into her entire being until she felt completely numb. Her lungs felt as if they were going to burst in her chest. Spots danced across her field of vision.

Every thought, every emotion racing through her grew sluggish. Dimly, she knew she was going to drown, but the fear behind it was gone. She could merely accept it as she was pulled farther and deeper into the sea.

Letting out what remaining air she had, she closed her eyes succumbed to the inevitable. At least it was better than any of the other methods she had considered.

What she was not expecting to feel were strong arms wrapping around her waist and water rushing past until there was nothing but hard-packed sand beneath her. She was not expecting hands that pumped the water out of her lungs or lips against hers that breathed air back into her chest.

Alphys gasped and coughed, too weak to do more than open her eyes. Her limbs felt like they were made of lead. She could only blink as she focused on the face of the person who saved her, just close enough for her to see clearly.

It was a face she never forgot.

A young woman with long, straight red hair leaned over her, peering down with eyes that almost looked maroon. Her skin was blue. Around her eyes, on the ridges of the frills on either side of her head, and in the gills that cut into her neck was bright red. Standing out among it all was the brilliant red of her lips. Fangs glinted behind them as the woman tilted her head to get a better look at her.

Whatever Alphys was looking at was not human- that much she knew- along with the fact that she was very beautiful, in a rugged sort of way.

And very naked.

When it was apparent Alphys was alive again, the woman stood. "Be careful," She said, and her voice was deep and as roughly alluring as the rest of her.

She turned and ran toward the waves, and Alphys just managed to push herself up to watch her dive back in. She thought she saw the tip of a ruby tail dip above the water before every trace of the woman was gone.

-

Alphys never forgot. For weeks afterward, the woman lingered on her mind. The way she stuck out against the grey sky like a jewel. How her skin seemed to shimmer in the light like scales. How her coloring was so contrasting yet so striking all at once.

How, even if it was just for a moment, and even if it was for survival, her lips had been pressed against Alphys'.

As ridiculous as it was, the only explanation for the odd anatomy of the woman was that she was some sort of aquatic creature. And the most reasonable one was a mermaid- it even could be the reason for the tail she thought she saw.

Every scientific part of her brain fought against the thought of it. Mermaids didn't exist. Everyone knew that.

But if the woman wasn't a mermaid, what was she? And why was it that Alphys found herself at that same beach every day, waiting for something to happen?

Odd things continued happening there, too. She would sometimes come across beautiful shells near shore that she knew were only found much deeper. Fish would sometimes race towards her as she was looking for samples, as if they were trying to flee from something. And once, on a particularly warm day, she had fallen asleep, only to wake up with an old towel draped across her. Because of it, she avoided most of a bad sunburn.

She had kept the towel.

No matter what happened, though, she never saw the woman.

After an especially poor day, she had driven straight to the beach instead of home and had stomped out into the shallows. She was scaring away all the specimens, but she didn't care. She just wanted to be in the sea.

She went deeper without thinking until the water was mid-thigh. She felt the sting of tears in her eyes and wiped at them stubbornly. She tried to take a deep breath and took another step.

Suddenly, a flash of blue and red flashed just beneath where her foot was about to fall. Alphys stumbled back, nearly falling as the creature circled around her and slowed, holding a fish in it's hands that she recognized with horror.

She had nearly stepped on a stonefish. A sting from it was both incredibly painful and possibly lethal. She really must have not been paying attention to where she was going.

"Geez. You have really shitty luck with the ocean, you know that?"

The voice came from behind her. Alphys spun around and was face-to-face with the woman she had been searching for.

A tail came out of the waves and slapped against the water on it's way down. Alphys felt like she might pass out. She didn't imagine it after all.

The woman grinned, revealing row after row of fangs, and Alphys' heart leapt to her throat for a variety of reasons. "You humans are always so jumpy when you first see me."

Alphys could only blink. "Y-you're a mermaid," She said, more statement than question.

"You're a human." She raised the fish in her webbed hand and pointed at it. "This is a stonefish."

Alphys couldn't keep back a slight laugh. "Yes, I-I know. I'm a m-marine biologist."

It was the mermaids turn to be confused. "A what?"

Alphys raised her bag of samples. "I study ocean life."

"Oh! I thought you were just hunting this whole time." The mermaid flipped onto her back and floated idly by. "Why do you do that?"

Alphys wasn't used to talking to people for so long. Especially pretty girls. "W-well, to u-understand the o-ocean better so we d-don't disturb it t-too much. A-and because I like doing it."

She snorted. "You guys don't do a very great job with not disturbing us."

Alphys dropped her gaze. "I know. Th-that's what I'm t-trying to change."

The mermaid's tail drifted past, and Alphys noticed it had to be at least seven feet long. She couldn't tear her eyes from it. "A-are you a shapeshifter?"

"Hm?"

"The time you, um, s-saved me. You had l-legs."

There was a long pause, and Alphys wondered if she said the wrong thing. She dug her nails into the skin of her palm, becoming more and more anxious with every passing second. S _tupid, stupid, you always say the wrong thing..._   


"I can be humanlike just as long as I can hold my breath," She said slowly, as if it wasn't something she was supposed to say. "But not much longer. I'm Undyne, by the way."

"A-Alphys," She stammered out. "That's my name."

Undyne swam closer and grinned wider, pushing her hair out of her face. Alphys noticed a long scar over her right eye, sealing it shut. "Were you attacked?" The words stumbled out before she could stop them. "Y-your e-eye, I mean."

Undyne let her hair fall again, partially obscuring the scar. Her eyes narrowed. "A human got a little too close to my territory, and when I tried to chase him out, he gave me that." And then her grin returned. "But I sure gave him hell! He never came back here again. Notice how this beach is so empty?" When Alphys nodded, she continued. "They say there are sharks here, so no one comes. But there aren't. It's just me."

Alphys wasn't sure which would be worse when it was after someone. Undyne's fangs would definitely hurt, and her arms and torso were so well muscled...

She swallowed hard. _Get your head out of the gutter._ "Y-you never a-attacked me, though."

Undyne shrugged. "It's not like you ever took more than you needed, and you stayed in the shallows. Some of you guys, you bring out these huge boats and take so much fish I have to switch hunting grounds! But you aren't like that."

She flipped around in the water, looking toward the horizon, and Alphys could only stare at how defined her back was.

"Wow! It's that late already?"

She looked up and saw the sun was setting. Her eyes widened. "I-I didn't even notice."

"I'll have to be getting back soon."

Undyne started swimming away, but Alphys stepped forward again. "W-Wait! Will I ever see you again?"

Undyne turned back to her. "Will you come to this beach again?"

She nodded. "I come here e-every day."

"Then you definitely will."

She dove under the water and was gone.

And, suddenly, the red of the sun against the blue of the sea could only remind Alphys of one thing.

-

Every day after that, she met Undyne at the beach. She started wearing her swimsuit under her clothes, and Undyne would show Alphys her favorite places in the sea, usually staying where Alphys could easily swim back.

At first, it was hard for her to go out in just her swimsuit. She wasn't fat, but she wasn't skinny, either, and she was always self-conscious about it. And next to Undyne's brilliance, she used to feel she seemed even more plain. Her hair was dirty blond, her skin was pale, and her eyes were just a boring shade of brown- nothing like the breathtaking features Undyne had.

But Undyne never seemed to notice that. In fact, the more time she spent around her, the more Alphys' confidence grew.

Today was one of those days.

"Alphys, this way!"

She followed Undyne's voice as she swam toward a rocky outcropping. They dotted the ocean all over the place in the shallower parts. Alphys had never gone very close to them, though.

"Hurry, before the tide comes in!"

She pushed herself to go just a bit faster, trying to keep her breath even. She was a bit out of shape. "I'll be right there!"

Undyne was leaning against the stone when she got there, halfway out of the water. Alphys forced her eyes up to her face.

"You'll have to climb up over the rocks to see it. I think it'll be easier to get up from here." She patted the rock beside her. "I'll swim around and meet you on the other side. Sound good?"

She looked up at the rock nervously. It wasn't very tall, and it was pitted with holes, but she wasn't all that strong. "I'm not sure if I can..."

"You can do it! I believe in you!"

Alphys took a step forward and reached toward where the rock jutted out. "From here?"

Undyne nodded, and she pulled herself up, searching for the next handhold. She found it and, little by little, inched her way up the rock. She was out of breath already. She persisted.

Undyne whooped and threw up her arm, her hand in a fist. "Look at you go! Keep it up, Alphie!"

She flushed and almost lost her hold. She wasn't used to the nickname.

"I'm going to swim around to the other side. I know you'll be able to get to the top. See you there!"

She heard a splash and knew Undyne was gone. Nervousness suddenly overcame her, and she froze in place. What if she didn't make it? She would fall back in and drown. Undyne might not save her again.

No. If Undyne said she could do it, she would do it. She narrowed her eyes and pulled herself up over the side of the rock and collapsed on the top, chest heaving. This was the first time she had overcome her anxiety.

"The champion arrives! The crowd goes wild! Woooooo-wee!"

Undyne came out of the water in a great arc, flipping midair before crashing back down into the waves. Alphys could only stare, amazed. Was she trying to show off for her?

She surfaced again and pulled herself up to sit beside Alphys. Her long tail hung over the rock, the tips just brushing against the water. "I love this place. It's so relaxing."

Alphys was so caught up in her, she completely forgot to look at where Undyne had taken her. She tore her eyes from her face and looked around.

She gasped.

The rocks formed a crescent around them, with only a gap at the front letting anything in. Coral grew in little patches, surrounded by other oceanic plants. Fish of all sorts swam among them. It was like a little cradle of life.

"I thought it was too cold for coral to grow," Alphys breathed, taking it all in with wide eyes. "This is incredible!"

"The rocks keep out most of the cold water, and it's shallow enough to stay warm. Of course, the tide comes in and makes it deeper, but it's not enough to disturb it all." She smiled contentedly. "It's like a little paradise."

Alphys stared at it, amazed. The ocean stunned her a little more every day. She loved it more than anything else.

Well, up until recently, she did.

As a comfortable silence stretched between them, Alphys became more and more aware of Undyne's presence like a magnet beside her. Eventually, it was all she could think about. She found herself stealing glances at Undyne. Her gaze lingered a little longer each time.

It settled on her hand. At the webbing between her fingers. On her fingernails, which were almost like claws. And suddenly, she could only think of one thing.

She gave in.

She moved her hand a little closer. When there was no reaction, she slid her hand over until their fingers brushed. She gulped. Her heart was pounding. She stared at the water, her face red, waiting for something to happen.

She heard a little giggle from beside her that made her chest tighten. Undyne put her hand over Alphys', gently, and gave it a squeeze.

Alphys could die happy, then and there.

"You're cute."

She didn't hear that right. "Wh-what?"

Undyne turned to her and grinned, the sun setting behind her. It was like something out of a picture. "You're cute."

Alphys just stared at her, her mouth slightly ajar. She didn't know how to respond. "Thanks! You're, uh, s-super pretty, too!"

Undyne laughed a little and looked back down, humming a little under her breath. After a moment, she spoke again. "Tell me about what it's like for humans."

Alphys started speaking and didn't stop. She told her about everything- her little apartment, the busy city she lived in, the kind of technology she had. She glanced over periodically at Undyne, worried she was boring her. Every time, though, she looked captivated, nodding along avidly.

Alphys was sure of one thing, at least.

Undyne didn't move her hand.

-

Alphys took a step back from the drop-off, eyeing the deep water warily. "Oh, I d-don't know..."

Undyne ran her hand through her hair, grinning, and Alphys felt her breath catch. "C'mon! It'll be fine, I promise. If anything happens, I'll take you back to the shallows." When Alphys still looked uncertain, Undyne swam back toward the giant rock formation. "Here, watch."

She dove under the water and disappeared. A few seconds later, Alphys heard a splash.

"See! It's easy!" Undyne's voice echoed from inside the rock. A moment later, she surfaced outside and beckoned to Alphys.

At least the water wasn't as cold as it used to be. With the warmer weather, she could stand being in the ocean longer, which lead to Undyne taking her out farther and deeper. But she never had to do anything like this before.

She gulped, steeling herself. Glancing over to Undyne encouraging her once more, she took a deep breath and swam under. If she thought Alphys could do it, she would try her best.

She opened her eyes again, trying to clear her bleary vision. She had kept her new glasses on, but they didn't do much against the salt. It still stung.

She followed Undyne deeper into a crevice in the side of the rocks, slipping through into a dark cavern. She saw a glimmer of light above and frantically pushed her way toward it until she broke the surface, gasping for air. It took longer than she estimated to get inside.

Undyne whooped. "Look at that! I knew you could do it!" She gave Alphys a hearty clap on the back that was a little too strong. Alphys knew she meant well, though.

For the first time in ages, Alphys genuinely laughed. "I d-didn't think I c-could," She said, quietly.

"I did."

Alphys' eyes were still adjusting to the gloom, so she couldn't see Undyne's face, but she could imagine it- the kind of smile where all of her fangs were showing with her eyes crinkled at the corners. When Alphys first saw it, she was a little intimidated, but now she thought it was beautiful. It seemed so free.

"Soon, you'll get so great at swimming, you'll be able to go to all my favorite places out here! It'll be like you were a mermaid yourself."

Alphys sighed wistfully. "If only."

Undyne didn't respond. Something suddenly felt uneasy. Alphys looked around the cavern as her eyes finally adjusted, trying to find another topic to redirect whatever went wrong.

"Oh wow," She breathed.

It was more of a grotto than a cavern. Ocean plants grew in dense patches in the sand beneath her, and she could see fish darting about in them. High above, there was an opening in the rock, and the blue of the sky shone through. It was like something out of a photograph.

"This is one of my favorite places to sleep." Undyne said, looking at the cave fondly. "The water is calm enough so it won't disturb me, and there are plenty of fish about if I get hungry. It's pretty great. Watch this!"

Undyne slipped back under the water and swam down. Not taking her eyes off her, Alphys swam backward until her feet could touch the sand again, since the grotto was shallower on one side. Undyne was completely still at the bottom of the cave, her hair spread around her in the water. She stood out vividly against the green backdrop of the plants. She tensed as a fish moved near her. A second of calm passed before she struck lightning-fast, shooting back up to the surface.

She burst out in front of Alphys, flipping her hair back out of her face. She held the fish above her like a trophy, still wriggling in her hand. It was brownish-grey and spotted- a flounder.

"Did you see that?!" Undyne threw her head back and laughed. It was bubbly and loud and a little rough, and it made something tighten in Alphys' chest. She wanted to hear Undyne laugh all the time. "That was awesome! I totally wrecked this fish!"

Alphys looked up at the helpless thing and felt a little sorry for it. "Y-yeah, I saw it. That was g-great! You're really strong and cool and pretty-"

She cut herself off before it could get any worse. Undyne didn't respond, and Alphys could feel her self-hatred increasing by the second. Why do I always, always have to mess things up...

"Uh, thanks! You're really cute and smart and stuff too!" Alphys looked up to her, surprised. It was too dim to be totally sure, but Alphys could have sworn Undyne was blushing. "Are you, um, hungry?"

Her eyes went to the poor flounder, still twitching in Undyne's hand. "No, I'm good."

Undyne let the fish drop. It lay motionless in the water for a moment before it started swimming again, back to the bottom of the grotto. At least it was alive.

Alphys was about to speak when a shiver went through her, cutting off her speech. It was colder in the grotto, especially in the water, and Alphys was feeling it's effects. She rubbed at her arms.

"Oh, are you cold?" She could see Undyne's expression clearly now. Her brow was furrowed, and her head was slightly cocked to the side. She was concerned.

"I-I'm a-alright." It was hard to speak clearly when she was shivering. It made her stuttering even more apparent.

Undyne looked around the cave, as if trying to find something. Then, seeming to give up, she swam closer to Alphys. "I hope this is, um, okay," She said, sounding embarrassed, before she hugged Alphys.

For a long, long moment, all Alphys could feel or think about was the press of Undyne's body against her's, and her heart seemed to be pounding in her throat. Her breath came just a tiny bit faster. She could feel her arms, her stomach, her chest...

_Stop it. Don't make this weird._

"I-It's f-fine," She stammered out. Her voice squeaked out higher than usual.

When she got her mind back under control, she noticed just how warm Undyne really was. It was strange, since they were in the water. "Y-you're a-actually, um, u-unusually w-warm for the water and air temperature. Do you know why?"

She could feel Undyne shrug against her. "I think it's because we live in colder water a lot of the time. We have to be warmer naturally to withstand that, right?"

That made sense. "S-sorry, I just d-don't know much about mermaid biology."

Silence stretched between them. Alphys hugged her back, tentatively. She rested her head on Undyne's shoulder. It was nice. It was really, really nice. She closed her eyes.

"I wasn't completely honest with you."

Alphys couldn't stop herself from saying it. She felt Undyne stiffen beneath her, but only slightly. "What do you mean?"

Alphys took a deep breath. Way to ruin a moment. "I'm not a marine biologist. Well, not anymore." When Undyne didn't respond, she closed her eyes again and steadied herself.

_It's just like climbing rock walls. Just like diving under water. You can do it if you try hard enough._

She opened her eyes again and started speaking.

She told Undyne about the accident.

It started a while ago, after she had been an environmental toxicologist for a few years. She was still trying to deal with her anxiety and had a crush on her boss, who was too hung up on his ex-wife to notice her. It wasn't a good time.

Her group was running tests on a small tank that contained a controlled oceanic environment. It had taken months to build it to the point it was at, and it was a fragile balance. They had to be incredibly careful with the kinds of pollutants they introduced.

Alphys trailed off. The next part would the hardest to tell.

"And?" Undyne prompted, her voice surprisingly gentle. She hadn't spoken the entire time. "What happened after that?"

_Just like diving..._ The air suddenly felt like knives as she took a deep breath. "I was in charge of the next test and... I screwed it up." Her voice broke. "I put in too much of the pollutant, and I killed a ton of the fish. They had worked on it for months, and I just ruined it." She was close to tears, and she gripped Undyne's shoulder. Undyne didn't push her away, though. She just held Alphys all the tighter.

"I got fired. And I, um, started to hate myself. I mean, I always did, but it was worse. A lot worse. But I didn't want to be away from the ocean, so I started to come to get samples to study at home. I don't know why. I think I just wanted to have something to do." She could already feel the regret setting in. She hated telling people about her problems. She was always a burden to everyone.

"What happened after that?" Undyne's voice had gone soft. She just sounded sad.

"It got w-worse. My problem, I mean. And I..." She swallowed hard. It was much harder to say aloud than it was to think. "I didn't really want to live anymore. B-but then I m-met you, and I'm doing better, so it's o-okay! I haven't th-thought a-about it for a solid w-week and that's great!"

There was another pause. Alphys' regret grew with every passing moment. Now she had driven away the only person she could call a friend. She should have never opened her mouth in the first place.

Undyne finally spoke. She parted from Alphys, putting her hands on her shoulders and looking her in the eye. Her voice wasn't probing or insensitive. It seemed like she was just sad and concerned. "Why did you want to die?"

It all came out.

Suddenly, she couldn't keep back the tears. Months of repressed emotions resurfaced, and she started sobbing uncontrollably, pressing her hand over her mouth.

"It's b-because I'm fat and ugly and everyone hates me and I'm always just a burden and I can't do anything right and- and-" She couldn't speak as another sob wracked her body.

"No! No, no, none of that is true! I could never hate you. Never! And your hair is such a pretty color, and you have the cutest freckles out of any human I've ever seen!"

Alphys couldn't believe what she was hearing. Undyne continued.

"And who cares if you have a little extra fat? That's badass! That just means you're a good hunter, and don't have to worry about getting cold in deeper water. It looks good on you, anyway!"

Alphys wiped at her eyes with shaking hands. "You're j-just being nice."

"No, I'm not. You're really great, Alphys. You're really smart. You care about the ocean a lot, too, and you know so much about it. You always care a ton about whatever you tell me about. That's so awesome!" She smiled at her, just a little. "I love spending time with you like this, really. It's my favorite thing. I would never, ever want you to leave."

Alphys sniffed. Her tears had stopped. "It's the s-same for me. You're the b-best thing that ever happened to me, Undyne, and I don't e-ever want to leave you, I..."

She trailed off as Undyne cupped her cheek and leaned in.

The world could end, and Alphys wouldn't even notice. The ground could split apart beneath her feet, and she wouldn't care.

Undyne was kissing her.

Her lips moved so softly against Alphys'. Her hand slid back and tangled itself in her hair, the other bringing her closer until she was pressed up against Alphys.

At first, she was too stunned to respond. Undyne liked her. Undyne _loved_ her. It was enough to nearly make her cry again. She leaned in, her hands gently caressing Undyne's back. She felt light, her heart racing, her thoughts going even faster. Her hands wandered. Undyne sighed into her mouth. Alphys couldn't believe this was really happening.

They parted, slowly, and she rested her forehead against Undyne's. She was a little short of breath.

"Can you come here tomorrow morning?" Undyne's voice was a little rough. "I need to talk to you about something."

"Of course."

Undyne stroked her cheek, kissing her once more before she let her go and dove back under the water. Alphys followed.

It was especially hard to say goodbye. Alphys couldn't stop smiling.

-

Alphys came to the beach the next morning early. The sun was just beginning to rise, and the beach was calm. She didn't usually wake up before noon, but today, she had reason to be excited.

She sat down in the sand, taking off her sandals and stretching out her legs until the waves just reached her feet. The water was lukewarm. The sound of the waves relaxed her until her eyes drifted closed. Even when she was buried under blankets and watching her favorite show, her apartment had never felt like this much of a home.

The sound of a splash startled her back to alertness. She looked up, blinking as she adjusted her glasses. Undyne was there in the shallows. Alphys was suddenly consumed by nervousness- what if Undyne hadn't meant what she said yesterday, or if she changed her mind, or if she regretted it, or...

But she just smiled at Alphys. "You looked so peaceful. I didn't want to disturb you."

Alphys felt herself blush and looked down, fidgeting with the fabric of her dress. She wore it both because it would be easy to take off and because she thought she looked cuter in it. "Oh, um, thanks!"

When she didn't say anything else, Undyne cocked her head to the side. "Are you going to come in? It's not very cold. And I'm pretty hot and all, too." Right after she said it, she laughed. "Yeah, that sounded way smoother in my head."

If Alphys thought she was blushing before, it was worse now. "Y-you are, though."

"Hm?"

"You're, uh, really hot! I think! Yeah!" Alphys spun around and took off the dress, trying to control her embarrassment. Undyne whistled at her. She couldn't help laughing then.

She left the dress next to her umbrella- it wasn't very expensive or anything, so she didn't mind if it got sandy- and went into the water, bracing herself against the cold. As soon as it reached her stomach, Undyne came over and embraced her .

"I'm glad you came," She said.

"Of c-course!" Alphys still wasn't used to Undyne's attention. She felt like she would burst from happiness every time. It was like a dream come true. "But what did you need to talk about?"

Undyne let her go, swimming away a little. She ran her hand through her hair, thinking. "We should probably go somewhere first. It might take a while."

"The reefs?" Alphys suggested.

"That's a great idea." She grinned wolfishly. "Race you there!"

"I'm not going to win that!"

Undyne just laughed as she dived back under the water. Alphys followed behind, smiling and shaking her head a little.

As expected, Undyne was completely out of sight by the time Alphys reached the rocks, even though she had really been trying to go fast. She looked up at the rock wall, intimidated.

_Come on. If you could tell her about the accident, you could do this._

She took a deep breath and launched herself at the rocks, climbing up at a faster pace than the first time. When she got to the top, she was entirely out of breath and her arms were shaking. Some things never changed.

A moment after she reached the top, Undyne leapt out of the waves, water cascading down her as she landed a little awkwardly beside Alphys. She adjusted her position until she could sit comfortably and tossed her hair back. "Look at that! You beat me!"

"You let me win."

She looked skeptical. "Maybe it was your giant ripped muscles."

She stared at Undyne for a moment before bursting into laughter. She pushed herself off the rocks and flexed. "Heck yeah it was!"

Undyne flexed back, and Alphys felt her mouth drop open a little. She was really, really attractive.

Undyne tried to calm down, but a little laugh escaped again. "You're great, Alphie."

She scooted a little closer, taking Undyne's hand in her own. "So are you."

Alphys looked down at the reefs and watched the wildlife go about. She heard a sigh from beside her and looked back over to Undyne. The smile had fallen from her face.

"I wasn't totally honest with you, either."

Alphys furrowed her brow. "With what?"

"The whole human thing. I didn't tell you the whole story." She stared down at the water. "Any mermaid can turn completely human for a while. I don't mean just get legs, either. I mean completely human. It's how we usually reproduce. I'm just not good at it." She gestured to her tail. "If this dries out enough, I'm supposed to turn human. But it never has worked with me. I've only gotten to the point that you've seen. And I can only hold it for a few minutes. But..." She turned to Alphys and smiled. "I can still give it to someone else. And if I did, they would be able to turn into a mermaid, but I couldn't turn human anymore. I've never been able to, anyway, so it wouldn't make a difference!"

Everything seemed to slow down. Alphys looked over to Undyne, her eyes wide. "Are you offering this to me?"

Undyne misinterpreted her shock. "You don't have to accept, of course! And you should think about it a lot before you say anything. I mean, mermaids aren't that common, so you probably wouldn't see any more of us, and you would be giving up your humanity for me which is a huge sacrifice, and it's completely fine if you turn me down-"

"No, th-this amazing!" Alphys broke into a wide, dimpled grin. "I don't even like being a human much, and I've always wanted to be near the sea. This is perfect!"

It was Undyne's turn to be shocked. "Really? I mean, you would still be able to turn into a human for a full day, so you could go back for a while if you wanted, too! I've never heard of a mermaid having bad eyesight, either, so that should be fixed! But there's no going back. I won't be doing anything until at least tomorrow so you don't make any choices you'll regret."

"Okay. But I d-doubt my choice will change."

Undyne leaned over and hugged her tightly. Alphys returned the embrace.

"I usually hate all this sappy shit," Undyne said. "But for some reason, it makes sense to me when you're around."

Alphys smiled. "Whatever it is, I h-hope it never stops."

-

That evening, Alphys really thought about it. The more she did, though, the more certain she was of her choice. She didn't have a family or a job or even pets to keep her back. The next morning, she didn't bring anything with her. When she got to the beach, Undyne was already there.

"Alphie! Hey!"  
She could tell Undyne had been worrying. Her hair was messy, and she had been swimming in circles when Alphys approached. She waved back from the shore. "Hi!"

She didn't wait for an invitation this time. She entered the water and waded out to where Undyne was, but this time, Undyne kept a bit of a distance. She looked uncertain.

"I don't mean to rush you, but..." Undyne dropped her gaze and inspected her nails. It was the first time Alphys had seen her nervous.

"It's o-okay. I've decided, anyway." Undyne's eyes flew up to hers. "It hasn't changed or- or anything like that. I want to go with you."

The smile on Undyne's face could power an entire solar system. It was like she couldn't believe it. "Are you certain?"

Alphys nodded. "I've never been m-more certain of anything. Well, besides loving you, o-of course."

It was Undyne's turn to blush. "There you go with the sappy shit!" Alphys giggled. "But, um, I agree. About loving you and all that."

Hearing her say it made Alphys even more certain. She stepped closer to her, and Undyne reached forward and kissed her again, holding her close. She tasted like sea salt.

"Close your eyes," She whispered, and Alphys obeyed. Undyne kissed her lightly on the forehead, then onto her lips again, her embrace tightening. Alphys felt something start to change- a warm tingle spread it's way up her legs and spread it's way through her. When Undyne broke the kiss, Alphys opened her eyes slowly and looked down at the tail that went up to her waist.

She felt powerful and comfortable all at once. When she felt at her neck, a set of gills were there. Her skin had even adopted a sheen to it.

"I must make a poor mermaid," She mumbled.

"Not true." Undyne grinned her signature smile, and it made Alphys' heart beat just a little faster. "I guess the humans were right about all mermaids being beautiful."

She felt her face redden, but she smiled, meeting Undyne's gaze. "They always were."

Undyne splashed her playfully before diving in. Alphys followed after her, full of new, weird sensations. Her gills expanded as they took in water. Her eyes adjusted to the salt easily.

Undyne turned back and reached out toward her. "Come on, Alphys. There are so many places I want to show you."

She smiled widely and took her hand.


End file.
